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SketchyLISP
Reference
  Copyright (C) 2007
Nils M Holm

union

Conformance: SketchyLISP Extension

Purpose: Compute the union of sets. Sets are represented by lists of unique members.

Arguments:
A*... - sets

Implementation:

(define (union . a*)
  (unique (apply append a*)))

Example:

(union '(a b c) '(b c d) '(c d e)) 
=> (a b c d e)

See also:
intersection, unique, member.